Pseudomonas aeruginosa exotoxin

Transforming growth factor-a-Pseudomonas aeruginosa exotoxin A 40 (TGFa-PE40, Mr = 44,960) is a recombinant fusion protein synthesized in E. co/z.127,128 The growth factor moiety binds to surface epidermal growth factor (EGF) receptors on cancerous cells and is internalized where it releases the exotoxin domain into the cytosol.128 The toxin subunit catalytically inactivates the protein synthesis machinery of the cancer cell and the cell subsequently dies.129 It is a recombinant protein intended to be an anticancer therapeutic. 

Fass, R., Van de Walle, M., Shiloach, A., Joslyn, A., Kaufman, J., and Shiloach, J. (1991). Use of high-density cultures of Escherichia coli for high level production of recombinant Pseudomonas aeruginosa exotoxin A. Appl. Microbiol. Biotechnol. 36, 65-69. 

V. choferae 01 O antigen fragments, conjugated to recombinant Pseudomonas aeruginosa exotoxin A (rEPA)... 

Wilson BA, Collier RJ (1992) Diphtheria toxin and Pseudomonas aeruginosa exotoxin A Active-site structure and enzymatic mechanism. In Curr. Top. Microbiol. Immunol. 175 27-41. 

Unlike diphtheria toxin, little is known about the structures required for the translocation of the enzymatic subunit of PT. In diphtheria toxin and Pseudomonas aeruginosa exotoxin A, the B moiety can be clearly subdivided into two distinct domains, one responsible for receptor binding, composed essentially of (3 sheets, and one responsible for translocation of the A subunits, essentially composed of a helices (Allured etal., 1986 Choe etal., 1992). There is no clear translocation domain in PT, and much less is known about the internalization step of PT, compared to diphtheria toxin and exotoxin A. 

Like other bacterial ADP-ribosylating toxins (e.g. diphtheria toxin. Pseudomonas aeruginosa exotoxin A, cholera toxin, pertussis toxin, and C. botulinum C2 toxin (Aktories and Just, 1993)), C3 is a mono-ADP-ribosyltransferase (Aktories et ai, 1988b). Treatment of ADP-ribosylated Rho with phosphodiesterase releases 5 -AMP and not phosphoribosyl-AIVtP, a cleavage product of poly(ADP-ribose) (Aktories et ai, 1988b Rubin ef a/., 1988). Accordingly, thymidine, an inhibitor of poly(ADP-ribose)polymerase, does not block C3-like ADP-ribosyltransferases, and can be included in C3 ADP-ribosylation assays to block poly-ADP-ribosylation reactions. 

Like diphtheria toxin. Pseudomonas aeruginosa exotoxin A requires low pH to act (FitzGerald ef al., 1980). In spite of this, it has not been possible to induce translocation of Pseudomonas toxin across the surface membrane by exposure to low pH. It appears that the toxin must be transported beyond the endosomes, possibly to the trans-Golgi network or even to the endoplasmic reticulum to find conditions required for translocation (Chaudhary et al., 1990). In fact domain III ends with an amino acid sequence that (after removal of a terminal... 

The bacterial RNase, barnase, linked to Pseudomonas aeruginosa exotoxin A or to a non-toxic deletion mutant of the toxin lacking the enzymatic domain, was found to be toxic to cells to a greater extent than either component alone (Prior et al., 1991 1992). A C-terminal KDEL sequence was required for toxicity. Cells resistant to the intracellular action of the toxin were also sensitive to the fusion protein. This... 

Madshus I H, Collier R J (1989) Effect of eliminating a disulfide bridge within domain II of Pseudomonas aeruginosa exotoxin A. Infect Immun 57 1873-1878. 

Wick MJ, Hamood AN, Iglewski BH (1990) Analysis of the structure-function relationship of Pseudomonas aeruginosa exotoxin. A. Mol Microbiol 4 527—535. 

Fig. 10. Purification of a recombinant protein Pseudomonas aeruginosa exotoxin A -capture step.

Teter, K. and Holmes, R.K. (2002) Inhibition of endoplasmic reticulum-associated degradation in CHO cells resistant to cholera toxin. Pseudomonas aeruginosa exotoxin A, and ricin. Infect Immun, 70, 6172-6179. 

Carroll, S. F. and Collier, R. J. (1987) Active site of Pseudomonas aeruginosa exotoxin A. Glutamic acid 553 is photolabeled by NAD and shows functional homology with glutamic acid 148 of diphtheria toxin. J. Biol. Chem. 262,8707-8711. 

Holt PS, Misfeldt ML. Biological eficcts of pseudomonas aeruginosa exotoxin A lymphoproliferation of T lymphocytcs in athymic mice. Eur J Epidemiol 1988 4(l] 25-32. 

Zehavi-Willner T. Induction of murine cytolytic T-lymphocytes by pseudomonas aeruginosa exotoxin A. Infea Immun 1988 56(1) 213-218. 

Michalkiewicz J, Stachowski J, Barth C et al. Effect of pseudomonas aeruginosa exotoxin A on IFN-gamma synthesis expression of costimulatory molecules on monocytes and activity of NK cells. Immunol Lett 1999 69(3) 359-366. 

Holt PS, Misfeldt ML. Alteration of murine immune response by pseudomonas aeruginosa exotoxin A. Infect Immun 1984 45(l) 227-233. 

Jenkins C , Swiatoniowski A, Issekutz AC et aL Pseudomonas aeruginosa exotoxin A induces human mast cell apoptosis by a caspase-8 and -3-dependent mechanism. J Biol Chem 2004 279(35) 37201-37207. 

Iglewski BH, Liu PV, Kabat D (1977) Mechanism of action of Pseudomonas aeruginosa exotoxin A Adenosine diphosphate-ribosylation of mammalian elongation factor 2 in vitro and in vivo. Infect Immun 15 138-144... 

Active Sites and Homology of Diphtheria Toxin and Pseudomonas aeruginosa Exotoxin A... 

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